Bacon could stand in the way of a proposed U.S.-U.K. trade deal, according to Fortune.

What happened?

Fortune reported that some United Kingdom officials are seeking to reach a trade deal with the U.S. and U.S. farmers in anticipation of their withdrawal from the European Union following Brexit, but U.S. Commerce Secretary Wilbur Ross has indicated that such a deal would require some rule changes by regulators.

According to Fortune, the Soil Association, a U.K. food safety group, recently issued a report listing U.S.-produced bacon with additives as a potential health risk posed by the potential agreement.

The pork additive ractopamine increases the weight of pigs before they are slaughtered, but it “has been found to cripple the animals,” Fortune reported. The use of ractopamine is legal in the U.S., but the EU banned it in 1996.

The report also cites chlorine-washed chicken, hormone-treated beef, and food colorants as sources of concern for U.K. consumers.

“Some of the key differences between U.K. and U.S. production — hormone-treated beef, GM crops, and chlorinated chicken — are becoming increasingly understood by British consumers,” the report stated, adding that there are “other areas where products imported from the U.S. could be produced under significantly different standards to our own.”

According to The Guardian, the report also pointed to the use of chicken litter as animal feed and genetically modified foods as sources of concern.